摘要
针对稠油油藏储层特征与开发现状,基于静态泡沫性能与驱油性能评价,复配了3种具备不同性能的表面活性剂,并研究了不同表面活性剂辅助CO_(2)驱油效果,明确了表面活性剂的主控性能。实验结果表明,表面活性剂S1,S2和S3辅助CO_(2)驱油对渗透率级差为3.0的非均质岩心水驱后采收率增幅分别为19.7%,13.2%和15.2%,优于直接注入CO_(2)的驱油效果,说明表面活性剂可以提高稠油油藏高含水阶段CO_(2)驱油效果。其增油机理主要为表面活性剂驱油贡献及其与后续CO_(2)产生的泡沫的驱油贡献。表面活性剂乳化能力越强,乳化现象越明显,驱油效率增幅越大;静态发泡能力越强,与CO_(2)在岩心中越容易产生泡沫;强发泡能力-弱稳定性表面活性剂与CO_(2)产生的泡沫更容易实现深部调驱。随着非均质岩心渗透率级差从3.0增至9.0,3种表面活性剂辅助CO_(2)驱油效果均不同程度地下降,其中S1辅助CO_(2)驱油的采收率增幅降至12.6%,相比于S2和S3,S1对岩心非均质性变化的适应性较强。因此,对于目标油藏,具备强乳化、强发泡能力且兼顾弱泡沫稳定性的复配表面活性剂S1辅助CO_(2)驱油效果最佳,对非均质性变化的适应性更强。
In light of the characteristics and development status of heavy oil reservoirs,three surfactants with different prop⁃erties were compounded based on the evaluation of static foam properties and oil displacement performance.The oil dis⁃placement efficiency of CO_(2) flooding assisted by different surfactants was studied,and the dominating performance of the surfactants was clarified.The experimental results show that the recovery factor of the heterogeneous core with a permeabili⁃ty ratio of 3.0 grows by 19.7%,13.2%,and 15.2%,respectively after CO_(2) flooding assisted by surfactants S1,S2,and S3,which is superior to the oil displacement by direct CO_(2) injection.This demonstrates that the surfactants can improve the CO_(2) flooding of heavy oil reservoirs in the high water-cut stage.The mechanism of enhanced oil recovery(EOR)is mainly manifested as the oil displacement contributed by surfactants and the foam induced by the surfactants with subsequent CO_(2).When the emulsifying capability of a surfactant is stronger,the emulsification will be more evident,and the increase in oil displacement efficiency will be larger;stronger static foaming ability makes it easier to foam with CO_(2) in the core;the foam formed by CO_(2) with the surfactant of strong foaming ability but weak stability is more favorable for deep profile control.As the permeability ratio of the heterogeneous core increases from 3.0 to 9.0,the oil displacement efficiency of CO_(2) flooding as⁃sisted by the three surfactants declines to varying degrees.The increase in the recovery factor of S1-assisted CO_(2) flooding reduces to 12.6%,and compared with S2 and S3,S1 is more adaptable to the heterogeneous changes in the core.Therefore,for the target reservoir,the compound surfactant S1 with strong emulsification,strong foaming ability,but weak stability per⁃forms best in assisting CO_(2) flooding for EOR.
作者
李晓骁
岳湘安
闫荣杰
郭亚兵
檀洪坤
LI Xiaoxiao;YUE Xiang’an;YAN Rongjie;GUO Yabing;TAN Hongkun(State Key Laboratory of Petroleum Resources and Prospecting,Beijing City,102249,China;College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing City,102249,China;SINOPEC Petroleum Exploration and Production Research Institute,Beijing City,100083,China;No.1 Oil Production Plant,PetroChina Huabei Oilfield Company,Renqiu City,Hebei Province,062552,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2021年第6期94-100,共7页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项“低渗-致密油藏高效提高采收率新技术”(2017ZX05009-004)
国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”(2016ZX05050012)
国家自然科学基金重点项目“致密油储层提高采收率关键理论与方法研究”(51334007)。
